Most barrel makers recommend fluting before the buttoning. I have fluted alot of barrels and have had no side effects, I believe that fluting is like everthing else there are good ways to do it and bad. You can flute a heavy 26" barrel with 6 - 1/4" flutes and usually get between 1/2 and 5/8 of a pound depending on depth. Radial fluting will take off 3/4 to 1.0 lbs but the minimum diameter of the flutes must be of a diameter that allows you to matain a sufficiently ridgid barrel.